Revolving door



July 9, E PEREN ET AL REVOLVING DOOR Filed Jan. 7, 1932 10 Sheets-Sheet 1 I T 2% 12/ Z I folvu/vp PERE/Y/ BY Chm/P455 AlSH.

ATTORNEY July 9, 1935.

E. PEREM! ET AL REVOLVING DOOR Filed Jan. '7. 1952 10 Sheets-Sheet 2 INVENTOR fDNU/VO PERf/W BY CHARLES KASH 777W ATTORNEY July 9, 1935. E. PEREMI El AL 2,007,213

REVOLVING DOOR Filed Jan. 7, 1932 10 Sheets-Sheet 3 INVENTOR ATTORNEY July 9, 1935. E. PEREMI ET AL REVOLVING DOOR Filed Jan. '7, 1932 10 Shets-Sheet 4 INVENTOR nu/vo PEREM/ ATTORNEY -iglnk llllllllll 1% 1 P.

JuIy 9, 1935. E. PEREMI ET AL REVOLVING DOOR Filed Jan. 7, 1932 10 Sheets-Sheet 5 INVENTOR [wry/v0 CHA 1?; E5

July 9, 1935. E. PEREMI El AL REVOLVING DOOR Filed Jan. 7, 1952 10 Sheets-Sheet 6 July 9, 1935. i E. PEREMI ET AL REVOLVING DOOR Filed Jan. '7, 1952 10 Sheets-Sheet 7 INVENTOR [an /v0 PEPE/1L BY CHARLES K/SH.

7%; ,L 77% ATTORNEY wk m y 9,1935. E. PEREMI ETAL 2,007,213

REVOLVING DOOR Filed Jan. 7, 1932 10 Sheets-Sheet 8 INVENTOR farm/v0 PEPE/"ll ATTORNEY July 9, 1935- E. PEREMI ET AL REVOLVING DOOR Filed Jan. 7 1952 10 Sheets-Sheet 9 I July 9, 1935. E. PEREMI AL.

REVOLVING DOOR Filed Jan. 7, 1932 10 Sheets-Sheet l0 wwkwm \NVENTOR 0Mu/v0 Pf/Pf/"l/ BY 57/45151 K/SH WM .A 2%

ATTORNEY Patented July 9, 1935 NT OFFICE- REVOLVING noon Edmund Peremi, Manhas set, and Charles Kis'h, Elmhurst, N. Y., assignors to General Bronze Corporation, Long Island City, N. Y., a corporation of New York .Application January '7, 1932, Serial No. 585,270

38 Claims.

This invention relates to revolving doors for buildings and has for an object the provision of an improved construction for the pivotal mounting of the individual leaves of the door whereby 5 the leaves are rigidly 'and firmly supported, and

will not sag, but which permits of the ready folding of the leaves, either when the door is to be foldedand pushed to oneside, or automatically where, as in theicase of panic, a rapid exit through i both sides of the door is essential. Other objects of theinvention relate to improved means for supporting the door so as to permit its being moved more. readily to one side when folded and being returned to operative position and centered in such position when it is to be unfolded and set for rotation. Another object of the invention is to provide an improved chain arrangement for releasably connecting the leaves of the door when unfolded. Other objects and advantages will appear from the following description of certain preferred embodiments of the invention which illustrate the principles thereof.

In the accompanying drawings which illustrate such preferred 'constructionsz 1 Figure 1 is a front elevation showing a door withthe leaves unfolded and set at right angles in normal operative position, a part of one leaf of the door being broken away and the door enclosure being shown in section.

Figure2 is a fragmentary View in vertical section through the central supporting column of the door, showing parts of the leaves and illustrating the slide which operates the. pivot by which the door is. centered at the bottom and. l the plunger for releasing the trolley latch..

Figure 3 is a horizontal section on line.3--3 of Figure 2. s

Figure 4. is a plan view of the door with leaves at right angles, the door enclosure being shown in sectional plan. This figure also shows in dotted lines the position of the door whenfolded and moved to one side.

Figure ,5 is a plan View of the floor socket for receiving the central pivot of the door, parts being broken away.

Figure 6 is a vertical sectional view showing the trolley for supporting the door and means for locking the trolley at the inner and outer limits of its travel. This figure also shows in section the hinge supports for the door leaves at the top the do r- Figure 7. is a plan view of the trolley, its tracks and the trolley locking means, parts being broken awa v Fi u e 3 a verti a s c alV ew show ng e hinge supports for the door leaves at the bottom of the door, and showing the bottom door pivot and its floor socket.

Figure 9 is a fragmentary, vertical, sectional view showing parts of the hinge construction taken on line 99 of Figure 8.

Figure 10 is a horizontal, sectional, view showing the hinge construction for the door leaves taken at the positionindicated by line Ill-ll] of Figure 8.

Figure 11 is a vertical section taken on line ll-H of Figure 10. 1

Figure 12 is a section similar to Figure 10 showing the door leaves folded.

Figure 7 13 is a horizontal section showing the parts in the position illustrated in Figure 12, the section, however, being taken slightly below the level at which the section of Figure 12 is taken and on a plane between the two supporting discs.

V Figure 14 is a horizontal section taken on line 20 i l-l4 of Figure 1, parts of the latch blocks being broken away.

Figure 15 is a-horizontal section on line iii-15 of Figure 16 showing a portion of one'of the door leaves on an enlarged scale and illustrating the details of the spring pressed latch mechanism for engaging thechain.

Fi ure 16 is a side elevation of the parts shown in Figure 15, the cover plate being removed.

Figure 17 is a section taken in the position illustrated. byline l"!- -l'l of Figure 16.

Figure 18 is a detail view in horizontal section showing the edge of one of the door leaves and the Weather stripping mounted thereon.

Figure 19 is a view in horizontal section similar to Figure 10, showinga-modified construction of means for releasably locking the door leaves in radial positions.

Figures 20, 21 and 22 are plan views on a reduced scale showing locking rings used in the modified construction.

Figure 23 is a vertical sectional view on line 2323 of Figure 19.

Figures 24 and 25 are diagrammatic plan views showing respectively the engagement of the locking bolt with the disc and with one ofthe lock-.- ing rings. V

Figure 26 is an end View of the locking bolt.

, Referring to the drawings in detail, the door comprises a central supporting column 20 upon which are mounted, by hinged or pivotal connections, the door leaves 2|,usually four in number. When the .door is in operative position the leaves are set at right angles to one another, as indicatedin Fig. 4, but the leaves may be folded up a finish for the column and also to form a weather tight engagement with the adjacent walls of the door leaves.

The edges of the door leaves are preferably provided with suitable flexible weathering strips 32. Figure 18 shows an improved weathering strip and means for anchoring the same to the door leaves. As shown in such figure, the weathering strip comprises a body 33, preferably of molded rubber and tapering in thickness from its base toward its outer edge. To the flexible edge of the rubber strip is secured a contact strip 34 preferably of felt or the like. The body 33 is anchored to the door by means of a channel member 35 of metal or wood in which is formed a Y- shaped groove 36. The rubber body 33 is formed with a base having diverging flanges 31 adapted to fit in the branches of the Y-shaped groove. Screws 38 may be provided at intervals as an additional means for securing the rubber strip in the channel member 35. The construction described provides a very firm and durable means for attaching the flexible weathering strip to the door leaf.

The door is suspended from above by a trolley construction shown more particularly in Figures 6 and 7. A track comprising a pair of parallel channel shaped rails 40 is mounted above the ceiling 23. Mounted to travel on the rails is a trolley comprising a frame 4| supported by wheels 42. The frame includes a transverse channel shaped member 43, supported upon which is a metal cup 44. The cup has a central opening through it around which is an upwardly projecting flange 45. Mounted in this cup and around this flange 45 is an annular block of rubber or other flexible material 46 upon which is mounted a flanged ring of metal 41 which carries a ball or roller thrust-bearing 48. Supported by bearing 48 is a collar 49 which is fixed to the upper end of the supporting tube 38 of the door-supporting column. The entire weight of the door is thus carried by the thrust-bearing 48 which permits free rotation of the door. The annular rubber block 46 provides for a limited amount of universal movement of the door supporting column with relation to the trolley and its tracks so as to permit the door to center itself with relation to its enclosure, and to rotate therein without binding, in case there is any imperfection of alignment between the trolley and the door enclosure. It also permits of the proper engagement of the bottom pivot of the door with the floor socket. Universal movement of the door column with respect to the trolley may be obtained in other ways, such as by the usual gimbal bearings, but the rubber block described provides ample freedom of movement for this purpose and is extremely simple and involves the use of a minimum of parts. Furthermore, no lubrication is required at that point, as would be necessary in the case of gimbal bearings. The rubber block is held firmly between the outer wall of the cup 44 and the inner flange 45 thereof, so that it will support the weight of the door without undue spreading. At the same time enough clearance is permitted to provide for the necessary movement of the column. The collar 49 may be fixed to the tube 38 in any suitable manner, for instance, by means of interengaging screw threads and the locking set screw 50. This arrangement permits of a limited vertical adjustment of the tube with reference to the collar so as to raise or lower the door slightly, as may be necessary to make it properly contact at ceiling and floor.

Two latches are provided, one at about the center of the track for the trolley, and one at one end of said track. One of these latches 68, is arranged to lock the trolley at its central position with the door column in alignment over the central floor socket, thereby permitting the bottom pivot of the door to be readily inserted in such socket; while the other latch 6| locks the trolley in its lateral position with the door folded at the side of the door opening as shown in dotted lines in Figure 4. The latches 68 and GI are of similar construction and each comprises a base 62 which is preferably adjustably mounted on the track structure and secured in adjusted position by bolts 83, passing through elongated slots 64 in the track structure. Each support 62 is provided with a stop 85 adapted to be engaged by the end of the trolley to limit the travel thereof. Each of the supports carries a pair of brackets 66 between which are pivoted the latch arms 81. Each latch arm 61 is provided with a cross-head 58 at the ends of which are mounted screws 69 which engage the top flanges of the tracks 48 and limit the downward movement of the arm 81. On the end of each arm is a lug 10 which has a vertical face on the side towards the latch support which is adapted to engage the face of a latch plate 1| on the trolley and hold the trolley at the limit. of its movement, while the other face of the lug is inclined as indicated at 12 so as to engage and ride over the inclined face I3 on the trolley latch plate when the trolley is being pushed towards the latch. It will thus be seen that when the trolley is being moved into latching position the face 13 will engage and lift the lug I8 and arm 81, the latch riding over the trolley latch plate II and engaging the latter by gravity when the trolley reaches the limit of its movement in engagement with the corresponding stop 65. Either latch may be adjusted longitudinally by loosening the bolts 63 and sliding the support 62 with relation to the track, such adjustment moving both the stop 65 and the latch arm lug 10 so that these two members retain their fixed relationship and engage and hold the trolley firmly in the desired position.

In order to release the latches the supporting tube 30 of the door has a plunger slidingly mounted in its upper end, such plunger terminating in a flanged head 8|. Each of the arms 81 has a pair of ears 82 projecting from its end between which is pivoted a detent 83. The latter has a nose 84, adapted to be engaged by the flanged head 8|, and a weighted arm adapted to hold the detent normally in the position shown in Figure 6 with the nose 84 projecting over the head 8|. Upon lifting the plunger it will be seen that the engagement of the head 8| with the nose 84 will lift the latter, which will carry with it the arm 61 and disengage the lug 18 from the edge of the trolley latch plate 1| thereby releasing the trolley and permitting it to be moved along the track. Such movement, however, will soon take the flanged head 8| out of engagement with the nose 84, thereby per- 7 E567 untilthe flanged. head 8i passesv the nose 84 which it may do on its downward movement, as-

will press down on; the nose and, raise the weighted, arm 85 until the flanged head has passed 13116,. 16I1d of the nose,. "whereupon the weighted, arm 85 will, restore the detent toits original position. and, the, nose 84 will project over the flanged headfi i. Uponliftingthe plunger and, head"- the latter will lift, the. nose 84: and thereby release the latch.

- The plunger 30, may be} raised and lowered in any'suitable manner, preferably by means of a rod Bllwhich passes downwardly through the-tube 3D toaislide ,9I,,(Fig.' 2,) mounted at some con- Venient point in the door column. The slide 9| may be actuated in any suitable manneras 'by means of a studQZ, projecting through, a bayonet slot 93 in the side of the column. Stud 92 may, if, desired, be provided with a socket 9,4 .inlits head for engagementby a. key or handle by which it maybe more readily manipulated.

The slide 9,,I is also preferably utilized to operatethe bottom pivot of the door by means of downwardly extending rodv 95, which has at its lower' end'a head 96. (Figure 8).. A sleeve -91 slides in the lower end ofv the tube 39 and is provided. at-the, top with a flange 98 which overlies the head'96. Secured in thesleeve 9'! isthe shank 9,9' Of-thBFbOttOlll pivot I68, the latter preferably terminating ina tapered portion IIlL. With this arrangement it. will. be seen. thatthe same movement'of. the stud 92 and slide 9| which: withdraws the bottomopivotfromits socket in the floor will raise the head 81150 as to release the latch'and permit the door supportingtrolley to: be moved. ;;When the, door is set in central position in its enclosure; the bottom pivot Hill isreceived in a socket set in the floor. be; employed, but I preferably utilizepthel I m!- proved socket illustrated in Figures 5 and. 8. r In theconstruction showrra cup IifiL-is set intothe masonry of the floor, this cup having near its upper end'an enlargement terminating in a flange 11.]; so as to. provide a circular recess; Mounted in the'irecess is a -socket plate H2: which has'a hole H3 therein which receives the bottom pivot IBIl. =.The;hole H3 is made slightly off-center with ref erenceto, the circumference of, thessocket plate,,as shown in Figure 5 so that .by rotation of thesocket plate in its: recess the position of the hole. H3- may be varied slightly with respect. to theqtruexcenter-of the floor socket. In this way a. limitediadjustmentis provided .for, and the hole 3- may be brought into proper alignment to receive the-bottom'pivot of the-door;v Thisis particularly useful in compensatingforslight in.- accuracies inisetting the socket in the floor. The

i socket plate maybe secured in its-recess in any desired positionby means of a number ofequally spaced screwslM. The cup IN) may be fitted."

may; be taken; ou a dv mp by emov Any: suitable socketmay:

the. socket plate. This arrangement avoids the necessityfor laboriously digging out dirt which may accumulate in the socket on occasions when preferably near the topand near the lower part thereof, are similar hinge or pivotal supports (Figures 6 and 8). Each of these supports comprises a pair of discs I26, I2I, firmly secured to the supporting tube: 30 of the central column in any suitable manner, as by means of flanges I22 and I 2'3fltting the supporting tube and secured thereto'by. means of screws IN. The bottom and top hinge constructionsof the door are substantially indentical' except that they are inverted with respect to one another. cally the bottom hinge construction shown in Figures 8 to 13', inclusive, it will be seen that the disc I20 is circular in form and the disc I is slightly largerthan the disc It!!! and is provided with a flange portion I25 which forms a circular recess=receiving the disc I 28. The periphery of thedisc I2I is of asomewhat angular outline as appears-in Figures 10, 12 and 13, and at each of the angles a vertically extending recess or notch I26 is formed, for a purpose to be explained. Each of the discs has cut through it a pair of double lobe cam grooves or tracks, the grooves in the disc [21 being indicated at I21 and the grooves inthe-disc I20 being indicated. at I28.

Considering specifi- I Betweenth'e discs is preferably placed a sheet'of metal 129 which prevents communication between the grooves in therespective discs.

The disc I2I has fixed in it two pairs of pintle studs I30 and I 3I which project from its upper surface. as shown in Figure 11. Disc I29 has two pairs-of similar downwardly projecting pintle studs- I32 and I33. The disc I'Zl also carries two fixed-studs I 34 arranged at opposite ends of a diameter near the periphery of the disc and projecting upwardly therefrom, and the disc. E26 care ries two corresponding downwardly extending fixed studs I35 arranged at opposite ends of a diameter at 90 to the diameter at the ends of which studs I34 are arranged. Each of the door leaveshashinge fittings MIJ set near the bottom thereof and I'M set near the top thereof. The hinge fittings I40 of two of the diametrically opposite leaves of the door are provided with hinge ea'rsxldl which overlie the disc I2I and which are providediwith recesses M3'adapted to engage the pairsof studs i323 and I3I, respectively, when the doors are unfolded to their normal radial pcsition' with respect to the axis of the door. The hinge fittingsv l ifimounted at-the lower parts of. the other two diametrically opposite door leaves are provided with hinge ears I46 which lie beneath the disci2l and. are adapted to engage the pair of studs. I32'and'I33, respectively, when the door is unfolded as'shownl in Figure 10. The lower hinge fittings of each of the first named pair of door leaves is provided withv a stud I58 carryinga: roller I5! adapted tormove in one of the cam grooves IZ'lin the disc I2I. Each of the'hinge fittings in the other'pair of. door leaves is provided with a'lstud I52 carrying'a roller E53 travelling inione of the cam grooves I28 in the disc I28. The hinge fittings. IA'IL at the topof the doorare constructed in the same way as the fittings-I40 except that they are inverted. In moving the door leaves from the unfolded or right angle position shown in Figure to the folded or collapsed condition shown in Figure 13, it will be seen that each door leaf is rocked about one or the other of its pair of pintle studs I30, I3I, I32 or I33 as the case may be and that during this rocking operation the roller mounted on the stud carried by the door fitting travels in the corresponding part of its cam groove in either the disc I20 or the disc I2I as the case may be. In this way the door leaves may be moved from a position at right angles to one another to a position in which all the door leaves are in substantial parallelism as shown in Figures 12 and 13. The position of the door leaves with respectto the discs I20 and I2I when the door leaves are folded or collapsed is maintained by engagement between one of the ears on each door leaf hinge fitting and its corresponding pintle stud in the proper disc and by the engagement of the stud rollers mounted in the door leaf hinge fittings with the walls of the cam grooves in the discs. When the leaves are moved to right angle or radial position as shown in Figure 10, however, it will be seen that the rollers on the door studs are each located at one of the cusps in the cam grooves in which position the roller does not extend the full width of the groove because it is necessary to provide a clearance at this point of intersection between the two curved cam groove lobes. Accordingly, in this position of the door leaves, play would be allowed between the door leaves and the central column, and the ears on the door leaves might move slightly out of engagement with the pintle studs on the discs. This movement, if permitted at the top hinge mounting of the door leaves, would permit such leaves to sag at the top away from the column and thereby prevent the door from fitting its enclosure properly and rotating freely. In order to hold the door leaves at all times in proper alignment and in true parallelism with the central column, provision is made of supplemental means to support the door leaves and maintain firm contact between the pintle studs and the ears on the door leaves when the door leaves are at the right angular unfolded position of Figure 10. These means comprise a block I60 pivoted in a recess in each door leaf hinge fitting and adapted when the doors are in the right angular position of Figure 10 to engage and bear against one of the fixed studs I34 in the discs I2I, or I35 in the discs I20, as the case may be. The blocks I60 are arcshaped at the back as shown at I6I (Figs. 10 and 12) and are provided with V-shaped faces I62 which engage the studs I34 or I35. The blocks I60 are mounted on pivots I65 rotatably mounted in the door hinge fittings as shown in Figure 8. Bullet catches I66 are also preferably mounted in the door hinge fittings, these catches engaging in one or the other of three recesses I61 formed in the adjacent faces of the blocks I60. The engagement of the bullet catch in one or the other of these recesses serves to releasably retain the block either in the central position shown in Figure 10 or in one or the other of. its partially rotated positions as shown in Figure 12. When the door leaves are set at right angular position as shown in Figure 10, the blocks I60 bear against their corresponding studs I34 or I35 and thereby prevent any movement of the door leaves out of their true positions in close contact with the central column. The ears at the top of the door leaves are also prevented from moving away from the corresponding pintle studs. When the door is folded, however, as shown in Figures 12 and 13, the blocks I60 are partially rotated by contact between the studs I34 and I35 and the corresponding walls of the V-shaped faces I62. The movement of the blocks out of contact with the studs I34 and I35 takes place at the same time that the rollers on the door studs move away from the cusp positions in the cam grooves and move into the curved parts of those grooves where they fit closely between thev groove walls and thereby support the door leaves in proper alignment. When the door leaves are restored to their right angular position, the tilted walls of the V-grooved faces of the blocks I60 engage their respective studs I34 and I35 and are moved back to the engaging positions shown in Figure 10. The bullet catches offer no substantial resistance to the movement of the door leaves but serve to maintain the blocks I60 in one or the other of the positions to which they are moved by engagement with the pins I34 and I35 and maintain the blocks in such positions until the door leaves are restored to right angular position. In this way the possibility of the blocks jarring out of position when the door leaves are folded as shown in Figure 12 is prevented and the blocks are at all times in a position to properly engage the studs I34 and I35 when the door leaves are moved back to right angular position.

It will be seen that in order that the door leaves may be closely folded as shown in Figures 12 and 13, it is necessary that recesses I10 be provided in the door leaves for the reception of certain of the pins I34 and I35 which would otherwise engage the two outermost of the folded leaves and prevent complete folding of the same into parallelism. These recesses have to pass entirely through the door so that any of the door leaves may be folded in either direction to the limit of permissible movement. In order to prevent drafts from blowing through such recesses, spring actuated flaps III are mounted on pins I12 in the door leaves. These flaps will yield in either direction when engaged by one of the pins I34 or I35 so that they do not interfere with the folding of the doors while they at all times prevent the passage of air through the openings in the door leaves. The door leaves are also provided with recesses I13 for clearing the hinge ears I42 or I44 on adjacent leaves, when the leaves are folded as shown in Figure 12. In order to prevent the passage of drafts through such recesses, weathering plates I14 (Figs. 10 to 13) are provided which extend across such recesses. The edges of the plates lie close to the central column when the door leaves are arranged in radial position (Fig. 10)

For the purpose of locking the door leaves in unfolded or right angular position, retractable bolts I80 are provided for engagement in the recesses I26 in the peripheries of the discs I2 I. The ends of the bolts are preferably of wedge shape, the recesses being correspondingly shaped, and the bolts are yieldingly urged into their recesses so that upon the application of sufficient pressure against any door leaf while another or others of the leaves are held stationary, the bolt will ride out of its recess and permit the door leaf to be folded. This permits the door leaves to be folded by the mere application of pressure without any manual releasing of latches or the like, and whenever it is desired to fold the door leaves it may be done in this way. The principal object of the yielding arrangement of the bolts, however, is

iii

to :make the door panic-proof-" whereby in case of an emergency if many people try to leave thebuildi-ng-by' the door and press-upon diametrically opposi'te leavesoi the door-at the same time; the

door leaves will yield and the door will fold there-v by permitting the crowd to pass out through both sides of the door. In a construction of this naturegit is necessary that the resistance of the boltsto the folding of the :door'leaves will be condesirable to have manual means for releasing the spring tension .when the bolts are to be withdrawnior thenormalzfolding of the doon-an'd thelfollowing construction has been provided for this purpose. Each bolt I has a hollo wshank. 1:81 into thevend of which screws a flanged bushing 182. Passing through the bushing is-a rod l 83which has a head 1B4 slida'blein the recess in thesbo'lt and adaptedlatxone end of its movement to engage with-the inner end of the bushing 1 82. The head I84 carries a pint I85, theuends of which projectninto, slots "186 in the shank of the bolt,

thereby preventing the head ,irom rotating with reference to the bolt.l As the bolt itself is rectangular and cannot rotate with respect to its housing,it will be seen that the' rodxl83 cannot rotate. The outer end of the rod I83 is screw threadedand screwsinto anut I81 in which is formeda longitudinal groove i 88. ...Compressed between the flange on the bushing and the nut i8! is astro'ng coiled" spring 189. which maybe put under a desired degree of initial compression by adjusting the nut I81 on the threaded end of the rod: 183. *Fixed on the outer end of the rod I83 i s-a collar 1'90 andfixed at an intermediate point: on the rod is a -stop ring .1 9|. The nut I81 may be adjusted longitudinally on the rod betweenthetcollar and the ring. For effecting this. adjustment a disc I 92v is provided which has akeyi engaging in the slot- I88: The edges of the disc project through slots H13 in theisides .of the door.

outer endof the rod 183' and the-collar I90 bear against a cam ['94 rotatably mounted in a recess in: thedoor fitting and having an exposed socket ladapted toreceive a key (shown in dotted lines in Figure 10,) by-whichitmay be-rotatedt The cam; has. a cylindrical face portion I96 and a flattenedeface portion I91, and abullet-catch I98 may be providedior engagement with one or. the 20131161 of two recesses in the cylindrical;

surface-of the cam so-as toyieldably lock the cam either inthe position shown in Figure 8' with a;-

portion of the cylindricalsurface of the cam bearing againstthe rod and collar or in a position at substantially right angles to theposi-tion, shownin Figure 8 in whichflthe'fiat of; the cam' faces the'end; of the rod and collar. .A stop J99:

isalso; provided in the" cam housing which positively stops theca-m-at the limits of itsrotativei movement.- 'When the oam is inthe position shown in"Figure 8,,the rod which of course carr-ie'sthe spring abutment nut is held insuch po-' sition as'to-iorce the bolt into its recess in disc I24 and-the bolt can: only be: forcedfrom its re:

cessx-by. Pressure sufii'cient. to. compress the spring [83; When the cam is turned to. the other po' movement of the door leaf. s

be retracted freely-so as to permit free Owing-to the fact-that the door leaves have a pivotal -movement-a bout one or the other of the pintle studswhich are displaced *from" the central axis of the door, it will be seen that thepath of movement ofiithe nose of the bolt 1-80 after leavingits -recess I 26 will be approximately on the arc indicated by the broken line A in Figure 310. This f act 'coupled with the fact that the periphery of the discl =2 l-is of generally angular form ratherthan circular, will cause the nose of the .bolt to move-away fromthe periphery of thedisc, rather than in contact with it-through a substantial arc; as would be the case the periphery of the discwere' circularand the door leaves'were pivotedto move about an axis concentric with the axis of the discs; Accordingly, excess friction and wear o'f the parts -isavoided because the noses of the bolts quickly move entirely out of contact with the periphery of the disc. 7 .1 Thestud 92 asshown in Figures 2' and 3 is pref-- erably -arranged so that-when the door leaves are at right anglea one of the leaves will-conceal the Istud opening 229 being provided in the leaf f'OIJthlSI purpose; Owing to the manner in which the .:leave'sswing; upon one or the other of the.

.s'ition,-however, the springand bolt assembly-"may swinging Y pin tle studs, the motion of the leaf will be away 7 leavesmove towardsand away from the'surface ofrth'e column when the doors areswung about theipintle studs andthe formation of such. faces in concave shape'ywith ,a curvature to-..fit the surface of the column, enables these faces. to be brought into-close contact-with the columnssura face; when the leavesare set inoperatingposi ,tion, thereby makinga weather: tight closure at vTheengagement of. the bolts I'8El in; re?" cessesi I 26 in the discs I21 manyinstanc'e's be suificient to maintain the door leaves in their.

right angular positionwithout the .use of. any 'ad-.

ditionalholding means for the door leaves. If, however, it should bede'sired to provide an additional-means for connecting the door leaves; to

c 4.0: 'jjc'I'hegmanner in which the .faces ofthe door oneanother to resist undesired collapsing of the door, any, well-known releasablexchain orllink" arrangement may be; utilized.- For: example, the chain arrangement shown in Figures 14 to l? may advantageously. be utilized, this arrangement presenting, certain valuable features of novelty: and'pbeing applicable toother, type of panicproofrevolving door as well as to the construc; tion above described. 4 In the construction shown in Figures 14 to 17,

a single chain- 200 is employed, the endsof which a'refixed to oneof the door leaves :at the points 201;. the :chain passing without breakthrough re-- cesses in the other three door leaves; At three' points in the chain corresponding-with the positions of-the' other three door leaves when'the leavesiare a-t right angles; substantially diamondshapedflinks: 202 are insertedand yielding engaging' devices are provided in the door leaves for yielding engagement with these diamond-shaped links which thereby serve to hold the door leaves normally at right angles but permit them to be moved upon the application of sufficient pressure. The yielding means in the door leaves comprise channel-shaped fittings 205 set in recesses in the leaves, each channel-shaped fitting being provided with a removable cover plate 206 secured to the fitting by screws 201 or in any other suitable manner. Mounted to slide in the channel fitting is a frame 208 which may be adjusted longitudinally by means of the screw 209 which may be rotated by a disc 2I0 having sockets therein for insertion of a pin. Slidingly mounted in the frame 208 is a latch block 2I I. Mounted in a cross member 2I2 of the frame is a screw 2I3 which carries a spring abutment 2 between which and the latch block 2| I is mounted a compression spring 2I5. The initial compression of the spring 2I5 may 'be determined by adjustment of the screw 2 I3. The face of the latch block 2 is notched or grooved as indicated at 220 for engagement with one of the diamond-shaped links 202. Slidingly mounted in the frame 208 outside of the diamond-shaped link 202 is an abutment block 22I which has a grooved face 222 for engagement with the diamond-shaped link. A cam 223 mounted on a pivot 224 in the frame 208 is arranged to engage and support the abutment block 22I. Cam 223 has a face 225 arranged to hold the abutment block in advanced position and it has a fiat face 226 which, when the cam is rotated a quarter turn permits the block 22I to move away from the latch block 2| I'. The cam may be rotated in any suitable manner as by means of a pin (not shown) inserted in a socket 221, a 'slot 228 being provided in the cover plate 206 for the insertion of the pin. When the block 22I is held in the advanced position shown in Figure 15, the door leaves can only be folded by applying a pressure great enough to depress the latch. bolt 2 to an extent sufficient to permit the points of the diamond-shaped link to clear both the abutment block 22 I and the latch block 2| I. By adjusting the screw 2 I3 any desired compression of the spring 2 I 5 may be secured and the resistance to the disengagement of the link 202 from the latch block made as great as is desired. If it be desired, however, to fold the door in the ordinary manner and without the application 'of considerable pressure, the cam 223 is rotated so as to permit the retraction of the abutment block 22 I. It will now be seen that the door it may become slack by moving out one or all of the frames 208 by adjustment of the screws 209. In the use of the chain arrangement described, the door leaves may be collapsed as soon as any one of the diamond-shaped links 202 moves out of engagement with the latch means on the corresponding leaf. As soon as this takes place, the other leaves may be folded by the doubling up of the stretches of chain between such remaining leaves. As long as all 'three'of the diamond-shaped links are in engagement with their respective leaves, however, allof the leaves are firmly held in proper angular relationship.

It is evident that the construction described will permit the door leaves to be folded into two parallel pairs placed at 180 from one another, as well as permitting all four of the door leaves to be folded parallel, as shown in Figures 12 and 13. As stated, the particular novel chain arrangement described, may be utilized in connection with the door construction illustrated and described or with any other suitable folding leaf door construction.

In the construction of door shown in Figures 1 to 13, it will be seen that each leaf of the door is releasably locked in radial position by its own bolt mechanisms which engage notches in the discs I2I fixed to the central column. In the event of panic each leaf is therefore capable of being folded independently by the application of pressure thereto, but the folding up of one leaf will not release the bolt mechanisms on the other leaves. The necessary force must therefore be applied to each leaf to overcome the resistance of the bolt mechanisms of that leaf before such leaf will collapse. In Figures 19 to 26, inclusive,'I have shown a modified construction of the door, such that as soon as the resistance to movement of any one of the leaves has been overcome, all of the leaves are immediately released so that they are all free to collapse or fold simultaneously. In this way free passage through the door is instantly provided, and there is no possibility of the door becoming jammed or interfering in any way with the free exit of a crowd of people trying to get through it rapidly.

Referring to Figures 19 to 26 in detail, it will be seen that the construction is generally similar to that shown in Figures 1 to 13. The door is provided with a central column including the tubular shaft 30 on which are mounted pairs of discs 250 and 25I, which are exactly similar to the discs I20 and I2I respectively, insofar as the various studs and cam grooves or tracks are concerned, which form the supporting and guiding' means for supporting thedoor leaves and permitting them to fold into collapsed condition.

Each disc 25I is provided with a narrow vertical flange 252 which fits the periphery of the body portion of the corresponding disc 250 and with an outwardly projecting flange 253 of circular outline. Each disc 250 has a similar outwardly projecting flange 254 and these two flanges enclose between them an annular recess 255 R0- tatably mounted in the recesses between each pair of discs are three rings 256, 251 and 258, each ofwhich is provided with an outwardly projecting perforated lug 259. Each of three of the door leaves is connected to a pair of these lugs 259 on the corresponding rings at the upper and lower door supports. The connection of each door leaf to its lugs is effected by means of a pivot 260 which connects the lug 259 with an ear or ears 26I projecting from a' slide block 262 mounted to slide freely in a recess 263 in the door leaf hinge fitting. It will be seen that the middle ring 251 is connected between a pair of ears 26I on the corresponding slide block, as shown in Figure 23. As will be readily understood, the car on the top ring 256 will be pivoted to a single ear on the second slide block of twice the thickness of the ears 26l shown'in Figure 23, while the lug 259 on the bottom ring 258 will be pivoted underneath a similar double thickness lug on the third slide block. It will be seen that when any of the three door leaves pivoted to one pair of these rings is swung about its hinge pine tles it will cause its rings to be rotated in the recesses 255. Each of therings is provided with a notch 265, the notches in the respective rings being arranged at 90 intervals with respect to the lugs 259 as shown-in Figures 20, 21 and 22.- The fourth leaf of the door is provided with a pair of latch bolts 180a which are similar to the latch bolts I89 previously described except as to the shape of the bolt face. Each bolt is provided with an adjustable spring assembly similar to that previously described, The flanges 253 and254 of each pair of discs and 250 are providedwith registering notches 210 adapted to be engaged by one of the locking bolts. Owing to the positions of the notches 265 in the three rings of each set, it will be seen that when the doors are in right angularposition, as shown in Figure 19, all the notches 265 will be in reg-.

istry and will, register with the notches 210 in the disc flanges. All of these notches will then be engaged by the locking bolts and all leaves will be held in radial position. Upon 1 applying force to the door leaf carrying the locking bolts,

it will be apparent that the boltswill ride out of the notches in the disc flanges, as in the construction shown in Figures 1 to 13, and this will cause the bolts to disengage the notches in the rings, so that all the door leaves will be immediately released and will fold freely to their collapsed position. Likewise pressure on any one of the other three leaves, sufiicient to move such leaf out of its right angular position, will rotate the rings to which it is attached and thus force back the latch bolts due to the engagement ofthe walls of the notches in such rings with the endsv of the bolts. This will result in releasing all the otherthree leaves. 1 V

In order that all of the leaves may present substantially equal resistance to'collapsing movement, the notches 2% in the rings are made more obtuse than the notches 210 in the flanges of the discs, as shown in Figures 24 and25, and the said 1 ends of the bolts are provided with obtuse central portions 212 for engagement with the notches in the rings and with more acute portions Zl'l for engagement with the notches in the flanges. Owing to the fact that the door leaf carrying the bolts {80a rotates about the. axis, of one or the other pairs of pintles I30, it will be seen that the angle between the plane of the notohwalls and the radius of rotation of the door is the angle X in Figure 24, As the axis of rotation of the rings, in the event that any other leaf of the door is first moved, coincides with the axis of the column, it will be seen that the angle between the plane of. the notch walls in the rings and the radius through the axis of rotation of the rings is made the same as the angle X described. Thus substantially equal force is required to push back the bolts whether this is done by engagement between the acute bolt faces 21! and the walls of notches m or between the obtuse bolt faces Z'liand the walls of notches 2%..

' The construction of revolving door described is applicable tofdoors made of any material, such as bronze, nickel, aluminum,fsteel or wood, or any combination of such materials and the door enclosure may be of such materials or .of such 5 .materials'in combination with marble .or the like.

'While we have illustrated and described in detail certain preferred forms of our invention, it is to beunderstood that changes may bemade therein and the "invention embodied in other 1 structures. We do not, therefore, desire to limit 1. Ina revolving door, a plurality of door leaves,

a centralcolumn carrying pairs of pivotal bearings fixed with relation thereto, at least one pair of pivotal bearings being provided for each door leaf, pairs of bearing members on the door leaves arranged to cooperate with the pivotal bearings'carried by the column, the bearing members on the leaves having bearing contact with the respective bearing members carried by the central column but being separable therefrom, each door leaf being arranged to have pivotal movement about one or the other of a pair of said pivotal bearings without previous circumferential movement, the pivotal axes of the respective pivotalbearing and their cooperating bearing members on the-door leaves being spaced from each other and from the axis of the colwhereby, when a door leaf is pivoted about one of said pivotal axes, the pivotal bearing and bearing member corresponding with the other pivotal axis will separate, and means for maintainingeach door leaf in assembled relation with respect to the columnwhereby at least one of the bearing members on said door leaf is maintained at all times in contact with the corresponding pivotal bearing. carried by the column.

' 2. In a revolving door, a central supporting column, a plurality of door leaves supported thereby and adapted to extend radially there- 7 from or to be pivoted with respect thereto, and means at each side of each door leaf providing separable pivotal connections between said door leafand column permitting said door leaf to be pivoted about an axis parallel with, but spaced from the axis of the column, the means providcolumn at one side of the door leaf separating when the door leaf is pivoted about the pivotal axis at the other side of the door leaf and vice versa, and means for maintaining the door-leaf in assembled relation with the column, so when 7 with the corresponding pivotal bearing member from each-other at each side of the leaf and being spaced from the axis of the column, pairs of bearing members on each leaf adapted to pivot on the corresponding studs, the pivotal connection between said bearing members and studs being separable, whereby the bearing member and stud on one side of the leaf willseparate when the door leaf is pivoted about the stud on. the other side of. the leaf, and meansfor maintaining the leaves assembled with respect to the column so when a door leaf is in radial position,

both pivotal bearing members on the leaf are;

umn, discs fixed on thetcolummpintle studsproing pivotal connectionbetweenthe door leaf and jecting from the discs near the column, and door leaves each having portions adapted to bear against and swing about adjacent pintle studs, grooves in the discs outside of said pintle studs and having portions" concentric with the respective studs and studs on the door leaves adapted to move in and be constantly confined and guided by said grooves as the doors pivot about said pintle studs, and means in addition to said grooves and the studs working therein for sup porting said doors in parallelism with said column when said doors are set in spaced radial arrangement about said column.

5. In a revolving door, a central column, discs fixed on the column, pintle studs projecting from the discs, and door leaves having portions adapted to bear against and swing about said pintle studs, grooves in the discs and studs on the door leaves adapted to move in said grooves as the doors pivot about said pintle studs, and means in addition to said grooves and the studs working therein for supporting said doors in parallelism with said column when said doors are set in spaced radial arrangement about said column,

said last named means comprising pins projecting from said discs, and blocks mounted in said door leaves adapted to engage and bear against said pins when said door leaves are in radial position.

6. In a revolving door, a central column, discs mounted on the column, pintle studs projecting from the discs, and door leaves having portions adapted to bear against and swing about said pintle studs, grooves in the discs and studs on the door leaves adapted to move in said grooves as the doors pivot about said pintle studs, and means in addition to said grooves and the studs working therein for supporting said doors in parallelism with said column when said doors are set in spaced radial arrangement about said column, said last named means comprising pins projecting from said discs, and movable blocks mounted in said door leaves adapted. to engage and bear against pins when said door leaves are in radial position, said blocks being pivoted to said door leaves to swing about vertical axes and having V-shaped faces adapted to engage and rest against the faces of said pins nearest to the axis of the column.

7. In a revolving door, a central column, discs mounted on the column, pintle studs projecting from the discs, and door leaves having portions adapted to bear against and swing about said pintle studs, grooves in the discs and studs on the door leaves adapted to move in said grooves as the doors pivot about said pintle studs, and means in addition to said grooves and the studs Working therein for supporting said doors in parallelism with said column when said doors are set in spaced radial arrangement about said column, said last named means comprising pins projecting from said discs, and movable blocks mounted in said door leaves adapted to engage and bear against pins when said door leaves are in radial position, said door leaves having openings extending. therethrough to receive said pins when the leaves are folded, and movable weather stops in said openings.

8. In a revolving door, a central column, discs mounted on the column, pintle studs projecting from the discs, and door leaves each having portions adapted to bear against and swing about adjacent pintle studs, grooves in the discs having portions concentric with the respective pintle studs and studs on the door leaves adapted to move in and be constantly confined and guided by said grooves'as thedoors pivot about said pintle studs, spring pressed bolts mounted in the door' leaves and movable in the planes of the leaves towards and from the central door column, and notches in the periphery of at least one of said discs adapted tofbe releasably engaged by said bolts, said bolts being forced back against said spring pressure by engagement with the walls of said notches upon the application of excessive pressure to said leaves.

9. In a revolving door, a central column, discs mounted on the column, pintle studs projecting from the discs, and door leaves each having portions adapted to bear against and swing about adjacent pintle studs, grooves in the discs having portions concentric with the respective pintle studs and studs on the door leaves adapted to move in and be constantly confined and guided by said grooves as the doors pivot about said pintle studs, spring pressed bolts mounted in the door leaves and movable in the planes of the leaves towards and from the central door column and notches in the periphery of at least one of said discs adapted to be releasably engaged by said bolts, said bolts being forced back against said spring pressure by engagement with the Walls of said notches upon the application of excessive pressure to said leaves, and means for manually releasing the spring pressure on said bolts.

10. In a revolving door, a central column, discs fixed to said columnnear the top and bottom of the door, two pairs of pintle studs projecting from each of said discs, two track grooves formed in each disc, each groove comprising two arc portions intersecting to form a cusp, each of said arc portions comprising circular arcs struck about an axis of one of said pintle studs as a center, four door leaves supported by said discs and having open sided bearings adapted to bear against said pintle studs and having concavely curved edge walls adapted to engage the surface of said column when said door leaves are set in radial position with respect to said column, each door leaf having a stud near the top and a stud near the bottom in axial alignment, each of said studs carrying a roller arranged to move in one of said track grooves, pins projecting from saiddiscs near the peripheries thereof, and movable blocks mounted in recesses in said door leaves adapted to engage with said pins and support said door leaves when the roller studs on said door leaves occupy positions at the cusp points in said track grooves.

11. In a revolving door, a collapsible door leaf assembly, a trolley, means for rotatably suspending said door leaf assembly from said trolley, a. bottom pivot for said door assembly, a fioor socket therefor, a track above the door on which said trolley runs, whereby said door assembly may be moved from a position central of the door enclosure to a position near one side of the door enclosure when the door leaves are collapsed and latch means for automatically engaging said trolley and holding it in a position in which the axis'of the door is centrally aligned with the door enclosure when the trolley is moved to its central position, prior to the engagement of the bottom pivot of the door with its floor socket.

12. In a revolving door, a collapsible door leaf assembly, a trolley, means for rotatably suspending said door leaf assembly from said trolley, a track above the door on which said trolley runs, whereby said door assembly may be moved from a position central of the door enclosure to a position near one side of the doorenclosure when the door leaves are collapsed and latch means for automatically locking the trolley atits side position.

13. In a revolving door, a collapsible door leaf assembly, a trolley, means rotatably suspending Said door leaf assembly from said trolley, a track above the door on which said trolley runs, whereby said door assembly may be moved from a position central ,of the door enclosure to a position near one side of the door enclosure when the door leaves are collapsed and latch means for automatically engaging said trolley and holding it in a position in which the axis of the door is centrally aligned with the door enclosure when the trolley is moved to its central position, prior to the engagement of the bottom pivot of the door with its floor socket, and latch means for automatically locking the trolley atits side position, and means carried by the door assembly for unlatching either of said latch means. l

14. In a-revolving door, a collapsible door leaf assembly, a trolley, means for rotatably suspending said door leaf assembly from said trolley, a track for said trolley, and latch means for the trolley comprising a movable latch member, a detent movably mounted on said latch member, and a plunger carriedv by said door assembly arranged to engage and lift said detent and latch member when actuated inone direction and-to move and pass said detent without moving the latch member when actuated in the opposite direction.

15. Ina revolving door, a collapsible door leaf assembly, a trolley, means for rotatably suspending said door leaf assembly from said trolley, atrack for said trolley, anda combined latch and stop for said trolley comprising a. support adjustably mounted on the track and-having a trolley stop thereon, said support also carryinga movable latch member adapted to engage a portion of the trolley and hold the trolley in engagement with said stop. l 16. In arevolving door, a collapsible door leaf assembly including a central column and door leaves supportedthereby, a trolley, means for rotatably suspending saiddoor leaf assembly from said trolley, a track for said trolley, a latch for locking said trolley in a predetermined position, a plunger carried by said door leaf assembly for actuating said latch, and actuating means for said plunger extending through said column to an accessible position and including a member adapted to be manually actuated, said member being arranged tobeconcealed by a door leaf when said leaf is, extended in radial position, but to be exposed when the doorleaf is collapsed.

' 17. In a revolving door, .a collapsible door leaf assembly including a central column,,and door leaves ca-rried thereby, a trolley, and means for rotatably suspending said door leaf assembly from said trolley including a thrust-bearing supportingthe upper end of said column and elastic means'for supporting said thrust-bearing upon said .trolley,.,

18 Ina revolving door, a collapsible door leaf assembly including acentral column,- and door leaves carried thereby, a trolley, and means .for rotatably suspending said doorleaf assembly fromsaid trolley including a thrust-bearing supporting the upper end of said column and elastic means for supporting said thrust-bearing upon said trolley, said elastic means comprising a flexible block interposed between said thrustbearing and the frame of said trolley.

19'. In a revolving door, a collapsible door leaf assembly comprising a column and door leaves pivotally connected therewith, a retractable bottom pivot for said door leaf assembly, actuating means in said column for raising and lowering said pivot, a studconnected with said actuating means by which the same may be manipulated, said stud projecting laterally through an opening in the wall of said column, one of said door leaves being arranged to conceal said stud when the door leaf is in radialposition and to expose said stud when said door leaf is collapsed.

20. In a revolving door, a door leaf assembly, means for rotatably suspending the same centrally' of the door enclosure, a bottom pivot for the door leaf assembly, a floor socket for receiving said bottom pivot including a member having a hole therein into which said pivot fits, and means for adjusting said member with respect to the socket so as to adjust the position of said hole with respect to the true center of the floor socket. v

1. In a revolving door, a door leaf assembly, means forrotatably suspending the same centrally of the door enclosure, a bottom pivot for the door leaf assembly, and a floor socket for receiving said bottom pivot, said floor socket comprising a cup set in the floor and a plate adapted to be secured to said cup in various rotated positions with relation thereto, said plate having an eccentrically placed, hole therein for receiving said bottom pivot.

22. In a revolving door, a door leaf assembly, means for rotatably suspending the same centrally of the door enclosure, a bottom pivot for the door leaf assembly, and a floor socket for receiving said bottom pivot, said floor socket having a removable dirt collecting receptacle therein.

23. Ina revolving door, a plurality of radially arranged leaves adapted to be collapsed about a central axis and means for releasably holding said leaves in angularly spaced relationship, comprising a single chainhaving its ends attached to one of said leaves and extending through openings in the other leaves and means at each of said openings for releasably gripping the chain to releasably fix eachileaf to the chain.

'24. In a revolving door, a plurality of radially arranged leaves adapted to be collapsed about a central axis andmeans for releasably holding said leaves in angularly spaced relationship, comprising a chain having its ends attached to one of said leaves and extending through openings inthe other leaves, said chain having enlarged links inserted therein at intervals corresponding to the normal angular intervals between the leaves, and means on each of the leaves, except that leaf to which the ends of the chain are fixed, for releasably engaging said enlarged links.

25. In a revolving door, a plurality of radially arranged leaves adapted to be collapsed about a central axis andmeans for releasably holding said leaves in angularly spaced relationship, comprising a chain having its ends attached to one of said leaves and extending through openings in the other leaves, said chain having diamond shaped links inserted therein at intervals corresponding to the normal angular intervals between the leaves and pairs of grooved blocks yieldingly pressed towards each other carried by each of said leaves, except the leaf to which the ends of said chain are fixed, said pairs of grooved blocks being arranged to releasably engage said diamond shaped links.

26. In a revolving door, a plurality of radially arranged leaves adapted to be collapsed about a central axis and means for releasably holding said leaves in angularly spaced relationship, comprising a chain having its ends attached to one of said leaves and extending through openings in the other leaves, said chain having diamond shaped links inserted therein at intervals corresponding to the normal angular intervals between the leaves and pairs of grooved blocks yieldingly pressed towards each other carried by each of said leaves, except the leaf to which the ends of said chain are fixed, said pairs of grooved blocks being arranged to releasably engage said diamond shaped links, and manual actuating means for relieving the engagement of one of the blocks of each pair from its corresponding diamond shaped link.

2'7. In a revolving door, a plurality of radially arranged leaves mounted to revolve about a central axis and adapted to be collapsed about said axis and means for releasably holding said leaves in angularly spaced relationship, comprising a single chain having its ends attached to one of said leaves and extending through openings in the other leaves, and means at each of said openings for providing yielding gripping engagement with the chain sufiicient to hold the leaves in normally spaced relation during the operation of the door, but arranged to permit collapsing of the leaves upon the application of abnormal pressure thereon, and a manually actuatable release for each of said gripping means.

28. In a revolving door, a central column, a plurality of leaves pivotally supported thereon, a disc carried by the column having a notch therein, a spring pressed bolt carried by one of said leaves adapted to engage the notch in said disc, a plurality of rings carried by said disc, one of which is connected to each of the other leaves of the door, each of said rings having a notch therein, said notches being so located in the rings that all of said notches will register with the notch in the disc and be engaged by said bolt when said leaves are in properly spaced radial positions.

29. In a revolving door, a central column, discs mounted on the column, pintle studs projecting from the discs, and door leaves having portions adapt-ed to bear against and swing about said pintle studs, grooves in the discs and studs on the door leaves adapted to move in said grooves as the doors pivot about said pintle studs, at least one of said discs having a notch in its periphery, one of said door leaves carrying a spring pressed bolt adapted to engage in said notch, a plurality of rings carried by said disc, one ring being pivotally connected to each door leaf, each ring having a notch in its periphery, said notches being so placed as to register with the notch in the disc and be engaged by said spring pressed bolt when said door leaves arein properly spaced radial positions.

30. In a revolving door, a central column, a disc mounted on the column, door leaves supported by the column and arranged to have pivotal movement with respect to said column whereby said leaves may be folded to collapse the door, and spring pressed bolts mounted in the door leaves, said disc and the ends of said bolts having parts formed to cooperate so as to hold said leaves in spaced radial positions around said column, said bolts being forced out of holding engagement with the corresponding portions of said disc upon the application of abnormal pressure to said leaves, each means for applying spring pressure to a bolt comprising a spring, a movable spring holding means therefor adapted to hold said spring under an initial minimum tension, and releasable abutment means for maintaining said spring holding means and the spring contained thereby in position to resist retractive movement of said bolt, each spring, and spring holding means being movable as a unit to and from effective position, and said abutment means being movable to a position permitting free retraction of said unit and corresponding bolt, so as to permit said bolt to be disengaged from said disc without stressing the spring and without modification of the initial minimum tension thereof.

31. In a revolving door, a central column, a disc mounted on the column, door leaves supported by the column and arranged to have pivotal movement with respect to said column whereby said leaves may be folded to collapse the door, and spring pressed bolts mounted in the door leaves, said disc and the ends of said bolts having parts formed to cooperate so as to hold said leaves in spaced radial positions around said column, said bolts being forced out of holding engagement with the corresponding portions of said disc upon the application of abnormal pressure to said leaves, each means for applying spring pressure to a bolt comprising a spring, a movable spring holding means therefor adapted to hold said spring under an initial minimum tension, means for adjusting such initial minimum tension, and releasable abutment means for maintaining said spring holding means and the spring contained thereby in position to resist retractive movement of said bolt, each spring, spring holding means, and spring adjusting means being movable as a unit to and from effective position, said abutment means being movable to a position permitting free retraction of said unit and corresponding bolt, so as to permit said bolt to be disengaged from said disc Without stressing the spring and without modification of the initial minimum tension thereof.

32. In a revolving door, a central column, a disc mounted on the column, door leaves supported by the column and arranged to have pivotal movement with respect to said column whereby said leaves may be folded to collapse the door, and spring pressed bolts mounted in the door leaves, said disc and the ends of said bolts having parts formed to cooperate so as to hold said leaves in spaced radial positions around said column, said bolts being forced out of holding engagement with the corresponding portions of said disc upon the application of abnormal pressure to said leaves, each means for applying spring pressure to a bolt comprising a coiled spring, a movable spring carrier for said spring comprising abutments for the ends of the spring and means for supporting said abutments in adjusted spaced relation so as to determine the initial minimum tension of the spring, and releasable abutment means for maintaining said spring carrier and the spring contained thereby in position to resist retractive movement of said bolt, each spring and spring carrier being movable as a unit to and from effective position, and said abutment means being movable to a position permitting free retraction of said unit and corresponding bolt, so as to permit 

